But, 26-year-old Vaibhav Vats will tell you, it was doing him no good. His weight had grown to 120kg and he was missing out on social life as he worked long overnight hours at a call centre. Eventually, he quit.

“You are making nice money. But the trade-off is also big," said Vats, who spent nearly two years at IBM Corp.’s call centre arm in India, answering customer calls from the US.

Call centres and other outsourced businesses such as software writing, medical transcription and back-office work employ more than 1.6 million young men and women in India, mostly in their 20s and 30s who make much more than their contemporaries in most other professions.

They are, however, facing sleep disorders, heart disease, depression and family discord, according to doctors and several industry surveys. Experts warn the brewing crisis could undermine the success of India’s hugely profitable outsourcing industry that earns billions in dollars annually and has shaped much of the country’s transformation into an emerging economic power.

Heart diseases, strokes and diabetes cost India an estimated $9 billion (Rs35,460 crore today) in lost productivity in 2005. But the losses could grow to a staggering $200 billion over the next 10 years if corrective action is not taken quickly, said a study by New Delhi-based Indian Council for Research on International Economic Relations.

The outsourcing industry would be the hardest hit, it warned.

Reliable estimates on the number of people affected are hard to come by, but government officials and experts agree that it is a growing problem. Health minister Anbumani Ramadoss wants to enforce a special health policy for employees in the information technology industry.

“After working, they party for the rest of the time... (They) have bad diet, excessive smoking and drinking," he said at a public meeting last month. “We don’t want these young people to burn out."

The minister’s comments have since infuriated the technology sector, which says it has been unfairly singled out for problems that also exist in other professions.

The outsourcing industry has come under fire because the sedentary lifestyle of its employees combined with often stressful working conditions makes them more vulnerable to heart disease, digestive problems and weight gain than others. Some complain of psychological distress.

Most call centre jobs involve responding to phone calls through the night from customers in the US and Europe—some of whom can be angry and rude. It is monotonous and there is little meaningful personal interaction among co-workers. That can also be true of other jobs such as software writing and back-office work.

“There are times when the stress is so overwhelming that they fail to cope with it. Then they come to us," said Archana Bisht, who set up a counselling company, 1to1help.net, in Bangalore six years ago.

Her clientele has since grown to 25 companies—seven of them were added in the past two months—including names as Intel Corp., IBM, Hewlett Packard Co. and Mindtree Consulting Ltd.

Each day, about 60-70 employees at these firms seek counselling from 1to1help.net. The complaints are many, but marital incompatibility and relationship issues top the list, Bisht said, often because the long, odd working hours mean couples don’t have much time together.

More women than men ask for help, she said. The outsourcing boom has created new employment opportunities for Indian women, but there has been little change in social expectations. Adding workplace demands to responsibilities at home, which often includes taking care of in-laws, leaves women workers with multiple stresses, Bisht said.

Loneliness can also take a toll. “There is no social life," said Vats, who worked at night and either slept or watched television during the day. “You are not meeting new people." The industry is getting sensitive to these problems.

The National Association of Software Services Companies, or Nasscom, the main trade body of the outsourcing industry, said many of its member firms are already providing facilities such as advice on health, gyms and money for regular checkups.

Companies such as Infosys Technologies Ltd have set up 24-hour helplines for counselling by psychologists, while others have tied up with companies like 1to1help.net. Some, such as HCL Technologies Ltd, have built daycare centres for children and routinely sponsor group outings for their employees.

But the industry insists it would do nothing to impose any lifestyle on its employees.

“We do not think it is for companies or for the government to interfere in the personal life of adult Indians," Nasscom said in a statement.

Also, there is little it can do to change the nighttime work hours of many outsourcing jobs.

“The odd hours can play havoc with your health," said Vats. “I never got good sleep because everyone was up and getting ready to go to work when I got home... Your diet goes for a toss. You get acidity, develop gastric problems."

Vats’ weight has dropped to 97kg since leaving IBM Daksh two years ago. He’s still overweight for his 5ft 9 inch frame, but is much happier now working with a law firm for a much lower salary.

Doctors say the rise in these diseases, alongside growing urbanization and fast-paced economic growth, is not surprising.

But India’s case is alarming because of the sheer number of people affected and the factors that make them vulnerable to these diseases, said Ravi Kasliwal, a cardiologist at New Delhi’s Indraprastha Apollo Hospital. These include India’s fat-rich diet, genetic factors make them highly vulnerable to diabetes, and abdominal obesity that gives rise to insulin resistance and heart disease.

“To top it all, there is lack of awareness," Kasliwal said. “One out of 10 persons aged 35 years or more in this country is prone to heart attack."

Heart disease is projected to account for 35% of deaths among India’s working age population between 2000 and 2030, Kasliwal said, citing a World Health Organization study.

That number is about 12% for the US, 22% for China and 25% for Russia.

“This is a very serious issue for this country," Kasliwal said. “But nobody wants to talk about it."